This invention relates to a hand-held power working machine, and in particular to a front handle and a handle protector which are disposed at a forward portion of the hand-held power working machine such as a hedge trimmer.
A hand-held power working machine such as a hedge trimmer is generally constituted by a prime mover case having a prime mover such as an internal combustion engine, a mount base portion surrounding a transmission case having a power transmission device such as gears to be actuated by the prime mover, a working portion comprising clipper blades to be actuated via the aforementioned power transmission device by the prime mover, and a handling portion attached to the prime mover case, the transmission case or the mount base portion. This handling portion is constituted, for the convenience of manipulation thereof, by a front handle portion and a rear handle portion. The front handle portion is provided in front thereof with a hand protector for protecting an operator's hand holding the front handle portion, while the rear handle portion is provided with a throttle lever for adjusting the opening degree of a throttle valve of the internal combustion engine.
FIG. 5 illustrates perspective views of a front handle 14' and a hand protector 20' which are ordinarily mounted on a conventional hand-held power working machine such as a hedge trimmer. As shown in FIG. 5, the front handle portion 14' is loop-shaped, the upper portion 14a' and both side portions 14b' of which being utilized as a gripping portion, and the lower portion 14c' of which being utilized as a fastening portion to be fixed to a tip mounting portion 12a' of a mount base 12' extending forward of the power working machine.
The hand protector 20' is formed of a single plate which has been bent into a L-shape, the rear flat protector portion 20a' of which is integrally connected through its rear end with the front portion of the lower portion 14c' of the front handle portion 14', while the fore flat protector portion 20b' of which is extended upward and inclined forward.
A transmission case (not shown) having a power transmission portion for actuating the work portion 13' consisting of the clipper blade, etc. is disposed at the forward portion of the power working machine, i.e. at the central scooped-out portion 12b' of the mount base 12' and below the front handle portion 14' and hand protector 20'. This transmission case is fixed via an elastic rubber (not shown) to the mount base 12'.
In the trimming work of hedge using the hand-holding power working machine (such as a hedge trimmer) which is provided with the front handle 14' and the hand protector 20', the working portion 13' consisting of clipper blades etc. is actuated while gripping the upper portion 14a' or the side portions 14b' of the front handle portion 14' with an operator's hand. During this operation, the hand protector 20' functions to protect the hand gripping the front handle portion 14'.
Since the conventional hand protector 20' as explained above is constructed such that the rear flat protector portion 20a' and fore flat protector portion 20b' thereof are, just like a cantilever, secured to and extended from the lower portion 14c' of the front handle portion 14', the rear flat protector portion 20a' is not only formed of a thin flat plate so as to lighten the weight of the hand protector 20' as much as possible and to assure a sufficient rigidity for ensuring the function as a protector, but also dimensioned to have a width "L" which is almost the same as the length of the lower portion 14c' of the front handle portion 14' so as to assure a sufficient rigidity thereof.
Meantime, there has been recently proposed a hand-held power working machine wherein a rear handle portion is rotatably mounted on the main body of the working machine and adapted to be locked at any suitable rotational position so as to conform it to any working posture of the operator. In the case of the working machine of this kind, it is required to secure the gripping position of the front handle so as to conform to any rotated position of the rear handle, i.e. as much area as possible of the loop of the front handle portion is required to be made available for gripping.
However, since the rear flat protector portion 20a' of the hand protector 20' is integrally connected, via its full width "L", with the lower portion 14c' of the front handle portion 14' according to the aforementioned prior art, the lower portion 14c' of the front handle portion 14' cannot be made available for gripping the front handle portion 14', thus making it difficult to suitably conform to the changes in working posture of the operator.
Moreover, since the loop-shaped front handle portion 14' is integrally connected with the hand protector 20' formed of a thin plate, there is a problem that should be improved, i.e. the manner of attaching these integrated bodies to the mounting portion 12a' of the mount base 12'.